Re: [PATCH v2 08/11] arm64/static_call: Fix static call CFI violations

Josh Poimboeuf
2023-03-22T18:26:26Z

On Wed, Mar 22, 2023 at 03:19:33PM +0100, Peter Zijlstra wrote:
> On Wed, Mar 22, 2023 at 12:22:07PM +0000, Mark Rutland wrote:
> > On Tue, Mar 21, 2023 at 09:00:14PM -0700, Josh Poimboeuf wrote:
>
> > > +++ b/arch/arm64/include/asm/static_call.h
> > > @@ -0,0 +1,29 @@
> > > +/* SPDX-License-Identifier: GPL-2.0 */
> > > +#ifndef _ASM_ARM64_STATIC_CALL_H
> > > +#define _ASM_ARM64_STATIC_CALL_H
> > > +
> > > +/*
> > > + * Make a dummy reference to a function pointer in C to force the compiler to
> > > + * emit a __kcfi_typeid_ symbol for asm to use.
> > > + */
> > > +#define GEN_CFI_SYM(func) \
> > > + static typeof(func) __used __section(".discard.cfi") *__UNIQUE_ID(cfi) = func
> > > +
> > > +
> > > +/* Generate a CFI-compliant static call NOP function */
> > > +#define __ARCH_DEFINE_STATIC_CALL_CFI(name, insns) \
> > > + asm(".align 4 \n" \
>
> Should this ^ be:
>
> __ALIGN_STR "\n" \

Ah right, you did mention that before. Will do.

--
Josh